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Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

Science china Earth Sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1,2,LIN XueHui1,2,YAO De3,4 & GUO WeiDong5 1 Key Laboratory of Marine Oil and Gas resources and Marine environment,Ministry of Land and resources,Qingdao 266071,china 2 Qingdao institute of Marine Geology,china Geological Survey,Qingdao 266071,china 3 institute of resources and environment,shandong university of technology,zibo 255049,china 4 institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,china 5 Department of Oceanography,Xiamen university,Xiamen 361005,china 1. Key Laboratory of Marine Oil and Gas resources and Marine environment Ministry of Land and Resources Qingdao 266071 China2. Qingdao Institute of Marine Geology China Geological Survey Qingdao 266071 China3. Institute of Resources and Environment Shandong University of Technology Zibo 255049 China4. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China5. Department of Oceanography Xiamen University Xiamen 361005 China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2 combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4＋ by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

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Floating Population Increase and Its Influence on the Urban Population Situation:A Case Study in Beijing

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Chinese Journal of Population,resources and environment 2005年第1期3卷 27-35页

作者： Wu Peilin 1,2 & Lu Qi 2 1. shandong university of technology, zibo shandong 255049, china 2. institute of Geographical Sciences and Natural resources Research, Chinese Academy of Sciences, Beijing 100101, china shandong university of technology Zibo Shandong 255049 China institute of Geographical Sciences and Natural resources Research Chinese Academy of Sciences Beijing 100101 China

Floating population is a special population group in china resulting from the implementation of household registration system. This paper uses a set of floating population survey data, population censuses data and statistical data to analyze the increase and influence of floating population on the urban population situations in Beijing. It is found that Beijing has experienced a rapid increase of floating population since the 1990s and that the increase of this group has become the key factor of the current population expansion in the city. Its distribution in the urban regions intensified and extended the suburbanization process of the capital. In addition, the population structures of sex, age, education and employment in Beijing have changed to some extent due to the influx of floating population.

关键词： Floating population Household registration system (Hukou) Population expansion Suburbanization Population structure Beijing

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Study on Human Capital Valve Quantity Model and Investment Featuers

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Chinese Journal of Population,resources and environment 2005年第1期3卷 49-54页

作者： Chen Peian, Li Yujiang & Li Zhen Population, resources and environment College, shandong Normal university, Jinan shandong 250014, china Population Resources and Environment College Shandong Normal University Jinan Shandong 250014 China

In this paper, human capital is considered a kind of goods in terms of investment. Basic consumption and profit margin are the two important components of human capital goods value. Compared with that of the material capital, the human capital consumption has the following features. The importance of human capital investment determined by the supply-demand mechanism, is growing gradually; The course of investment and return takes a long period of time; Human capital is characterized by strong technicality and weak negotiability; The investment profit margin is changeable and discriminating.

关键词： human capital value measure profit margin

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Immobilization of an enzyme from a Fusarium fungus WZ-I for chlorpyrifos degradation

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Journal of environmental Sciences 2010年第12期22卷 1930-1935页

作者： Hui Xie,Lusheng Zhu,Tingting Ma,Jun Wang,Jinhua Wang,Jun Su,Bo Shao College of resources and environment,shandong Agricultural university,Taian 271018,china [a] College of resources environment Shandong Agricultural University Taian 271018 China

The free enzyme extracted from WZ-I, which was identified as Fusarium LK. ex Fx, could effectively degrade chlorpyrifos, an organophosphate insecticide. The methods of immobilizing this free enzyme and determined its degradation-related characteristics were investigated. The properties of the immobilized enzyme were compared with those of the free enzyme. The optimal immobilization of the enzyme was achieved in a solution of 30 g/L sodium alginate at 4℃ for 4-12 hr. The immobilized enzyme showed the maximal activity at pH 8.0, 45℃. The maximum initial rate and the substrate concentration of the immobilized enzyme were less than that of the free enzyme. The immobilized enzyme, therefore, had a higher capacity to withstand a broader range of temperatures and pH conditions than the free enzyme. With varying pH and temperatures, the immobilized enzyme was more active than the free enzyme in the degradation reaction. In addition, the immobilized enzyme exhibited only a slight loss in its initial activity, even after three repeated uses. The results showed that the immobilized enzyme was more resistant to different environmental conditions, suggesting that it was viable for future practical use.

关键词： organophosphate pesticide immobilized enzyme degradation fungus

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Development and evaluation of an online monitoring single-particle optical particle counter with polarization detection

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Journal of environmental Sciences 2024年第4期138卷 585-596页

作者： Weijie Yao Xiaole Pan Yu Tian Hang Liu Yuting Zhang shandong Lei Junbo Zhang Yinzhou Zhang LinWu Yele Sun Zifa Wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the *** SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per *** SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal *** sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed *** calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3μm particles.T-matrix method calculations showed that the DR value of backscatter light at 120°could describe the variations in the aspect ratio of particles in the above size *** performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring *** instrument could provide useful data for source appointment and regulations against air pollution.

关键词： Instrument development Single particle detection Measurement uncertainty Optical simulation Mass concentration

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Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, china

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Chinese Journal of Population,resources and environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3, Zhang Zulu2, Jiang Luguang 1 1. institute of Geographical Sciences and Natural resources Research, Chinese Academy of Sciences, Beijing 100101, china 2. College of Population, resources and environment, shandong Normal university, Jinan shandong 250014, china 3. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china institute of Geographical Sciences and Natural resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2004, the spatial structure of Jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2004, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

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Multiple Effects of Energy Issues and Countermeasures: A Case of shandong Province

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Chinese Journal of Population,resources and environment 2008年第4期6卷 88-94页

作者： Wang Chengxin1,2 , Wang Gefang3 , Yao Shimou4 1. College of Population, resources and environment, shandong Normal university, Jinan shandong 250014, china 2. Research Center of Cycle Economy of shandong Province, Jinan shandong 250001, china 3. Party School of the shandong Committee of CPC, Jinan shandong 250021, china 4. Nanjing institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing Jiangsu 210008, china College of Population Resources and Environment Shandong Normal University Research Center of Cycle Economy of shandong Province Party School of the shandong Committee of CPC Nanjing institute of Geography and Limnology Chinese Academy of Sciences

Energy is now becoming the bottleneck of urban and regional development. The paper takes shandong Province, one of the most energy consuming provinces in china, as an example, uses quantity methods such as SPSS (Stastics Package for Social Science) cluster sampling and regression analysis, and applies quantity analysis, to analyze the situation of energy issues in shandong province. The conflicts between the quick industrialization and increasing extensive economic development, between urban population and energy consuming per head, between the infinite energy consuming desire and the low level of managing system, and between the unstable world energy supply and the limited energy storage in china are the main factors of energy crisis in shandong, which not only results in energy shortage, but also becomes the barrier of economic and social development. In order to ensure sufficient energy supply for shandong province in the 21st century, we should take countermeasures, such as changing the economic development model, pursuing a multiple and high quality energy strategy, improving the intensive urbanization strategy, and building a scientific energy system.

关键词： energy effects countermeasure shandong Province

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A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of environment Beijing Normal University Beijing 100875 China Department of Water environment China Institute of Water Resources and Hydropower Research Beijing100038 China Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3 & YE Xianren2 1. resources and environmental School, Lanzhou university, Lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, china 3. College of resources Science & technology, Beijing Normal university, Beijing 100875, china 1. resources and environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of resources Science & technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3He from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin

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Pedosphere 2005年第5期15卷 53-58页

作者： YUAN Fei 1,2, XIE Zheng-Hui1,* 2, LIU Qian1 and XIA Jun 3 1LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 (china). 2 College of Water resources and environment, Hohai university, Nanjing 210098 (china)3 institute of Geographical Science & Natural resources, Chinese Academy of Sciences, Beijing 100101 (china) institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 （china）. 2 College of Water resources and environment Hohai university Nanjing 210098 （china）3 institute of Geographical Science & Natural resources Beijing 100101 （china）

Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.25° × 0.25° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2 (1991-2100) and future climateB2 (1991-2100) with A2 and B2 being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2 and B2, theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 2031-2070. In addition,under future climate A2 and B2, an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin.

关键词： climate change regional climate modeling system runoff VIC-3L model

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